Ah, yes, I forgot about the quota rationale; we use independent filesets for that as well. We have run into confusion with inodes as one has to be careful to allocate inodes /and/ adjust a quota to expand a fileset. IIRC GPFS generates ENOSPC if it actually runs out of inodes, and EDQUOT if it hits a quota.
We've also run into the quiescing issue but have been able to workaround it for now by increasing the splay between the different schedules. On Tue, Jul 07, 2020 at 02:44:16PM +0000, Wahl, Edward wrote: > We also went with independent filesets for both backup (and quota) reasons > for several years now, and have stuck with this across to 5.x. However we > still maintain a minor number of dependent filesets for administrative use. > Being able to mmbackup on many filesets at once can increase your > parallelization _quite_ nicely! We create and delete the individual snaps > before and after each backup, as you may expect. Just be aware that if you > do massive numbers of fast snapshot deletes and creates you WILL reach a > point where you will run into issues due to quiescing compute clients, and > that certain types of workloads have issues with snapshotting in general. > > You have to more closely watch what you pre-allocate, and what you have left > in the common metadata/inode pool. Once allocated, even if not being used, > you cannot reduce the inode allocation without removing the fileset and > re-creating. (say a fileset user had 5 million inodes and now only needs > 500,000) > > Growth can also be an issue if you do NOT fully pre-allocate each space. > This can be scary if you are not used to over-subscription in general. But I > imagine that most sites have some decent % of oversubscription if they use > filesets and quotas. > > Ed > OSC > > -----Original Message----- > From: gpfsug-discuss-boun...@spectrumscale.org > <gpfsug-discuss-boun...@spectrumscale.org> On Behalf Of Skylar Thompson > Sent: Tuesday, July 7, 2020 10:00 AM > To: gpfsug-discuss@spectrumscale.org > Subject: Re: [gpfsug-discuss] dependent versus independent filesets > > We wanted to be able to snapshot and backup filesets separately with > mmbackup, so went with independent filesets. > > On Tue, Jul 07, 2020 at 08:37:46AM -0500, Damir Krstic wrote: > > We are deploying our new ESS and are considering moving to independent > > filesets. The snapshot per fileset feature appeals to us. > > > > Has anyone considered independent vs. dependent filesets and what was > > your reasoning to go with one as opposed to the other? Or perhaps you > > opted to have both on your filesystem, and if, what was the reasoning for > > it? > > > > Thank you. > > Damir > > > _______________________________________________ > > gpfsug-discuss mailing list > > gpfsug-discuss at spectrumscale.org > > https://urldefense.com/v3/__http://gpfsug.org/mailman/listinfo/gpfsug- > > discuss__;!!KGKeukY!j-c9kslUrEaNslhTbLLfaY8TES7Xf4eUCxysOaXwroHhTMwiVY > > vcGNh4M_no$ > > > -- > -- Skylar Thompson (skyl...@u.washington.edu) > -- Genome Sciences Department (UW Medicine), System Administrator > -- Foege Building S046, (206)-685-7354 > -- Pronouns: He/Him/His > _______________________________________________ > gpfsug-discuss mailing list > gpfsug-discuss at spectrumscale.org > https://urldefense.com/v3/__http://gpfsug.org/mailman/listinfo/gpfsug-discuss__;!!KGKeukY!j-c9kslUrEaNslhTbLLfaY8TES7Xf4eUCxysOaXwroHhTMwiVYvcGNh4M_no$ > > _______________________________________________ > gpfsug-discuss mailing list > gpfsug-discuss at spectrumscale.org > http://gpfsug.org/mailman/listinfo/gpfsug-discuss -- -- Skylar Thompson (skyl...@u.washington.edu) -- Genome Sciences Department (UW Medicine), System Administrator -- Foege Building S046, (206)-685-7354 -- Pronouns: He/Him/His _______________________________________________ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
